Method for producing semiconductor device and semiconductor device

Abstract

A method for producing a semiconductor device includes forming a first fin-shaped silicon layer and a second fin-shaped silicon layer on a substrate using a sidewall formed around a dummy pattern on the substrate. A first insulating film is formed around the first fin-shaped silicon layer and the second fin-shaped silicon layer. A first pillar-shaped silicon layer is formed in an upper portion of the first fin-shaped silicon layer, and a second pillar-shaped silicon layer is formed in an upper portion of the second fin-shaped silicon layer.

The invention claimed is: 
     
       1. A method for producing a semiconductor device comprising:
 a first step comprising:
 forming a first fin-shaped silicon layer and a second fin-shaped silicon layer on a substrate using a sidewall formed around a dummy pattern on the substrate; 
 forming a first insulating film around the first fin-shaped silicon layer and the second fin-shaped silicon layer; 
 forming a first pillar-shaped silicon layer in an upper portion of the first fin-shaped silicon layer, and 
 forming a second pillar-shaped silicon layer in an upper portion of the second fin-shaped silicon layer. 
 
 
     
     
       2. The method for producing a semiconductor device according to  claim 1  further comprises:
 after the first step, a second step comprising:
 forming first diffusion layers by implanting an impurity into an upper portion of the first pillar-shaped silicon layer, an upper portion of the first fin-shaped silicon layer and a lower portion of the first pillar-shaped silicon layer, and 
 forming second diffusion layers by implanting an impurity into an upper portion of the second pillar-shaped silicon layer, an upper portion of the second fin-shaped silicon layer and a lower portion of the second pillar-shaped silicon layer; 
 
 after the second step, a third step comprising:
 forming a gate insulating film, a first polysilicon gate electrode, a second polysilicon gate electrode, and a polysilicon gate line so that the gate insulating film covers side surfaces and upper portions the first pillar-shaped silicon layer and the second pillar-shaped silicon layer, the first polysilicon gate electrode and the second polysilicon gate electrode covers the gate insulating film, and where after the first polysilicon gate electrode, the second polysilicon gate electrode, and the polysilicon gate line are formed, an upper surface of a polysilicon region is located at a higher position relative to the substrate than the gate insulating film on the first diffusion layer in the upper portion of the first pillar-shaped silicon layer and the gate insulating film on the second diffusion layer in the upper portion of the second pillar-shaped silicon layer; 
 
 after the third step, a fourth step comprising:
 forming a silicide in an upper portion of the first diffusion layer in the first fin-shaped silicon layer and in an upper portion of the second diffusion layer in the second fin-shaped silicon layer; 
 
 after the fourth step, a fifth step comprising:
 depositing an interlayer insulating film, exposing the first polysilicon gate electrode, the second polysilicon gate electrode, and the polysilicon gate line, 
 etching the first polysilicon gate electrode, the second polysilicon gate electrode, and the polysilicon gate line, 
 then depositing a metal, and 
 forming a first metal gate electrode, a second metal gate electrode, and a metal gate line, the metal gate line being connected to the first metal gate electrode and second metal gate electrode and extending in a direction perpendicular to a direction in which the first fin-shaped silicon layer and second fin-shaped silicon layer extend; and, 
 
 after the fifth step, a sixth step comprising:
 forming a contact that is directly connected to the first diffusion layer in the upper portion of the first pillar-shaped silicon layer and the second diffusion layer in the upper portion of the second pillar-shaped silicon layer. 
 
 
     
     
       3. The method for producing a semiconductor device according to  claim 1 , wherein the first step further comprises:
 depositing a first oxide film on the substrate; 
 forming a first resist on the first oxide film; 
 etching the first oxide film to form the dummy pattern; 
 removing the first resist; 
 depositing a first nitride film; 
 forming a first nitride film sidewall around the dummy pattern by etching the first nitride film in such a manner that the first nitride film remains in a sidewall shape; 
 removing the dummy pattern; 
 etching the substrate using the first nitride film sidewall as a mask to form the first fin-shaped silicon layer and the second fin-shaped silicon layer such that they are connected to each other at their ends to form a closed loop; 
 forming the first insulating film around the first fin-shaped silicon layer and the second fin-shaped silicon layer; 
 removing the first nitride film sidewall; 
 etching back the first insulating film to expose an upper portion of the first fin-shaped silicon layer and an upper portion of the second fin-shaped silicon layer; 
 forming a second resist so as to be perpendicular to the first fin-shaped silicon layer and the second fin-shaped silicon layer; 
 etching the first fin-shaped silicon layer and the second fin-shaped silicon layer; and 
 removing the second resist to form the first pillar-shaped silicon layer such that a portion in which the first fin-shaped silicon layer is perpendicular to the second resist comprises the first pillar-shaped silicon layer and to form the second pillar-shaped silicon layer such that a portion in which the second fin-shaped silicon layer is perpendicular to the second resist comprises the second pillar-shaped silicon layer. 
 
     
     
       4. The method for producing a semiconductor device according to  claim 2 , wherein the second step further comprises:
 depositing a third oxide film on the after forming the second pillar-shaped semiconductor layer in the first step; 
 forming a second nitride film; 
 etching the second nitride film such that the second nitride film is made to remain in a sidewall shape; 
 forming the first and second diffusion layers by implanting an impurity into the upper portion of the first pillar-shaped silicon layer, the upper portion of the first fin-shaped silicon layer, the upper portion of the second pillar-shaped silicon layer, and the upper portion of the second fin-shaped silicon layer, respectively; 
 removing the second nitride film and the third oxide film; and 
 performing a heat treatment. 
 
     
     
       5. The method for producing a semiconductor device according to  claim 2 , wherein the third step further comprises:
 forming the gate insulating film so as to surround the first pillar-shaped silicon layer and the second pillar-shaped silicon layer; 
 depositing and planarizing a polysilicon such that an upper surface of the planarized polysilicon is located at a higher position, relative to the substrate, than the gate insulating film on the first diffusion layer in the upper portion of the first pillar-shaped silicon layer and the gate insulating film on the second diffusion layer formed in the upper portion of the second pillar-shaped silicon layer; 
 depositing a third nitride film; 
 forming a third resist for forming the first polysilicon gate electrode, the second polysilicon gate electrode, and the polysilicon gate line; 
 etching the third nitride film and the polysilicon to form the first polysilicon gate electrode, the second polysilicon gate electrode, and the polysilicon gate line; 
 etching the gate insulating film; and 
 removing the third resist. 
 
     
     
       6. The method for producing a semiconductor device according to  claim 2  further comprising:
 depositing a fourth nitride film after removing the third resist in the third step, 
 etching the fourth nitride film in such that the fourth nitride film remains in a sidewall shape, and 
 depositing a metal to form the silicide in upper portions of the first diffusion layers in the upper portions of the first fin-shaped silicon layer and second fin-shaped silicon layer. 
 
     
     
       7. The method for producing a semiconductor device according to  claim 6  further comprising:
 depositing a fifth nitride film after forming the silicide in the fourth step; 
 depositing an interlayer insulating film and planarizing the interlayer insulating film by chemical mechanical polishing, 
 wherein the first polysilicon gate electrode, the second polysilicon gate electrode, and the polysilicon gate line are exposed by the chemical mechanical polishing; 
 etching the first polysilicon gate electrode, the second polysilicon gate electrode, and the polysilicon gate line; 
 depositing a metal to fill portions in which the first polysilicon gate electrode, the second polysilicon gate electrode, and the polysilicon gate line are etched; and 
 etching the metal to expose the gate insulating film on the first diffusion layer in the upper portion of the first pillar-shaped silicon layer and the gate insulating film on the second diffusion layer in the upper portion of the second pillar-shaped silicon layer and to form the first metal gate electrode, the second metal gate electrode, and the metal gate line. 
 
     
     
       8. A method for producing a semiconductor device, the device having:
 a first fin-shaped semiconductor layer and a second fins-shaped semiconductor layer on a substrate; 
 a first insulating film around the first fin-shaped semiconductor layer and the second fins-shaped semiconductor layer; 
 a first pillar-shaped semiconductor layer on the first fin-shaped semiconductor layer; 
 a second pillar-shaped semiconductor layer on the second fin-shaped semiconductor layer; 
 a first gate insulating film around the first pillar-shaped semiconductor layer; 
 a first metal gate electrode around the first gate insulating film; 
 a second gate insulating film around the second pillar-shaped semiconductor layer; 
 a second metal gate electrode around the second gate insulating film, and 
 a metal gate line connected to the first metal gate electrode and the second metal gate and extending in a direction perpendicular to the first fin-shaped semiconductor layer and the second fins-shaped semiconductor layer; 
 the method comprising: forming the first fin-shaped semiconductor layer and the second fin-shaped semiconductor layer using a sidewall formed around a dummy pattern on the substrate.